An efficient porous molybdenum diselenide catalyst for electrochemical hydrogen generation

Abstract

The design and development of inexpensive and highly efficient electrocatalysts for hydrogen production underpin several emerging clean-energy technologies. In this work, we show a novel strategy to synthesize vertically aligned porous MoSe₂ by a two-step co-electrodeposition/etching method. The morphology of the porous MoSe₂ can be easily tuned by merely varying the Mo/Cu ratio. First, a matrix composite MoSe₂/Cu₃Se₂ was prepared by electrodeposition and Cu₃Se₂ was subsequently etched to form porous MoSe₂ structures. The obtained perpendicularly oriented porous MoSe₂ material exhibits an excellent electrochemical hydrogen generation catalytic performance without the need for a material transfer step. This designed architecture based on an oriented vertical structure possesses fully exposed active edges and open structures for fast ion/electron transfer, leads to remarkable HER activity with a low onset potential of −0.10 V vs. the RHE (reversible hydrogen electrode), a small Tafel slope of 46 mV per decade and excellent long-cycle stability. This work opens up a new class of nanomaterials for the development of efficient hybrid HER catalysts.